Apparatus for slack control



4 Sheets-Sheet l INVENTOR. W KM BY 9 A 7- Tog V575 mm U R. N. NEALIS APPARATUS FOR SLACK CONTROL Dec. 3, 1968 Original Filed Aug. 19, 1965 .3, 1968 R. N. NEALIS APPARATUS FOR SLACK CONTROL 4 Sheets-Sheet 2 Original Filed Aug. 19, 1965 INVENTOR. AKA/Sula ATTORNEYS Dec. 3, 1968 N. NEALIS APPARATUS FOR SLACK CONTROL 4 Sheets-Sheet 3 Original Filed Aug. 19, 1965 INVENTOR.

ATTOPNE Y5 Dec. 3, 1968 R. N. NEALIS APPARATUS FOR SLACK CONTROL 4 Sheets-Sheet 4' Original Filed Aug. 19, 1965 INVENTOR. W 1mm BY 94 ATTOR/VEKi United States Patent 3,414,134 APPARATUS FOR SLACK CONTROL Raymond N. Nealis, 11 Harvest Road, Levittown, Pa. 19056 Continuation of application Ser. No. 480,943, Aug. 19, 1965. This application Jan. 3, 1967, Ser. No. 629,837 11 Claims. (Cl. 213-43) ABSTRACT OF THE DISCLOSURE Apparatus for controlling slack between railroad cars including piston and cylinder means operatively connected between adjacent cars so that the relative motion between the piston and cylinder provides for slack, a fluid line between the cylinder chambers for conducting fluid between the same and mechanism in the line to stop the fluid flow and prevent the relative motion and thereby prevent slack.

This application is a continuation of my copending application Ser. No. 480,943, filed Aug. 19, 1965, now abandoned.

This invention relates to methods and equipment for improving the operation of railroad trains.

As is well understood by those skilled in the art, it is necessary to couple railroad cars by some mechanical means which provides for slack or relative motion between the cars. The term cars of course is inclusive of the locomotive providing the power source for the passenger, freight, mail or whatever cars make up the train.

The usual mechanical arrangement provides for an amount of slack just slightly less than two feet per car. In the so-called cushion type cars the slack between cars is increased to something in the order of five feet.

Slack is necessary in train operation in order to minimize the amount of power necessary to start the train from a standing position. Slack provides that the locomotive can pick up and move the car nearest to it, which in turn will pick up the next adjacent car and so on down the line. In general this reduces the power requirements that are necessary to pick up a loaded car and to overcome the effects of rolling friction on the cars which have already started to move. Without slack it would be necessary to provide several locomotives in order to move the train and indeed in many instances with say 200 car freight trains, it would be well nigh impractical to provide the locomotives and control forces to move the train.

While slack has the advantage as mentioned above it has several disadvantages which raise several serious op erating problems, an adequate practical solution to which has long been needed in the art.

For example, slack necessitates that stoppng the train be done only under so-called power braking conditions. The brakes are first applied and held in the on condition while the power output of the engine is slowly reduced. This, of course, is extremely wasteful of braking material and requires substantial track distance for the braking operation. It would be most desirable to reduce the locomotive power output and subsequently apply the brakes to bring the train to a stop. In this way the brakes work only against the momentum of the cars and not against the pulling force of the locomotive.

The reason power braking is used is that if the output of the locomotive were to be quickly decreased without braking, the cars behind it would be free to run in. The quick slack run in would cause severe impact on adjacent cars. This would result in damage to passengers, freight and draft gear. Indeed, this condition has oftentimes caused one or more pairs of adjacent cars to buckle and jump the tracks.

Patented Dec. 3, 1968 A decided disadvantage of slack and power braking is the effect of differences in velocities of the various cars. When the brakes are applied the cars will attain velocities dependent largely upon the weight, bearing and braking efficiencies. The velocities of some cars are reduced much quicker than others. One detrimental result of the foregoing is that the brakes on one or more cars may look the wheels, but the car is dragged along by other cars. This dragging effect causes flats on the wheels. Most times wheel flats will put the car out of service. Furthermore the difference in velocities and the slack causes impact as between slow and fast cars. Such impacts are a cause of injury to passengers and damage to freight and equipment.

Another serious disadvantage of slack is that it oftentimes results in the snapping of the couplings or wrecking of the draft gear between a pair of cars. For example, oftentimes when a train has been brought to a stop, the rear part of the train is on a descending incline. This causes slack run out in the rear part of the train as the train comes to a stop. Upon starting again, unless the engineer first backs up the train in a manner to eliminate the run out, the starting operation will result in snapping of the coupling of the cars adjacent the crest of the incline. This is due to the fact that the forward part of the train is moving and suddently it attempts to pick up all of the other cars from the rear part of the train. The forces involved are usually much greater than the forces the couplings are designed to stand.

The above are just a few examples of train operation to illustrate that acceleration and deceleration of a train is dependent to a large degree upon the skill and judgment of the engineer. Unless the engineer has had a great deal of experience so as to know how the different types and kinds of cars and their different loading characteristics function under acceleration and deceleration conditions, it would be virtually impossible to stop or start a train without an accident of serious consequences.

The present invention provides methods and equipment which will virtually eliminate all the several disadvantages which arise due to the presence of slack, yet maintain the slack as an integral and necessary part of the coupling arrangement between the cars.

In one broad aspect the invention contemplates a method for operating a train which provides for preventing slack between cars so that the cars, in effect, become a single unit prior to the time forces are introduced to cause deceleration, these forces being in the form of braking forces which are applied to the individual cars or in the form of back thrusts caused by reducing the power output of the driving locomotive, and in connection with the foregoing providing for slack to occur between adjacent cars prior to the time force is applied for acceleration, the accelerating force being in the form of increasing the power output of the driving locomotive.

One important advantage of the invention is that it is no longer necessary to power brake. The engineer is provided with means operable so that he can almost instantaneously prevent slack between the various pairs of cars and then immediately start to reduce the throttle. Under this condition substantial deceleration occurs without braking. To bring the train to a full stop, of course, the brakes are applied.

Another advantage of this invention is that it saves tremendous wear and tear on the brakes and hence substantially reduces maintenance and material costs.

Another very important advantage of the invention is that very substantial improvements in braking efliciency are attained. With all the cars locked together, so to speak, the individual braking forces applied are effectively integrated so that their sum total is available to stop the train. This is impossible under conventional methods of stopping because the individual cars attain different velocities. With slack elimination, all of the cars decelerate at the same rate or as one unit.

A particularly important advantage of the improved braking efficiency is that the train can be stopped in a much shorter distance. This enhances the flexibility of train handling and movement which enables, for example, the making of a more versatile signal placement at interlocking switches for diverting trains from one track to another.

F urther advantage of eliminating slack. prior to decelerating is that relative motion between the cars is prevented and hence there is no possibility of one car banging into another and causing damage to passengers, freight or equipment.

One of the most significant advantages of eliminating slack prior to deceleration is that it minimizes the necessity for high skill and judgment on the part of the engineer. No longer does the engineer have to consider the effects of individual cars. His only concern is with bringing the train as a whole to a stop.

To accomplish the foregoing, the invention contemplates a mechanism which is operatively interconnected as between two adjacent cars and functions to provide for or prevent slack between the cars. Preferably the mechanism is coordinated with both the braking system and the locomotive power control system.

The mechanism of the invention is coordinated with the braking system so that when the brake lever is in the off position, the mechanism provides for slack, but when the brake lever is thrown to the on position, the mechanism will operate to take out the slack prior to the time the brakes actually operate. The mechanism of the invention is tied in with the power control throttle so that when. the throttle is moved to decrease power output, the mechanism operates to prevent slack between the cars and when the throttle is moved to increase the power, the mechanism operates to provide for slack.

In its preferred embodiment the invention contemplates a pair of piston and cylinder devices which are disposed between adjacent cars, the devices being respectively connected between a car and the conventional coupler. Preferably each cylinder is connected to a car with a pivotal connection that provides for the cylinder to move in a horizontal plane and its piston is mounted on the coupling so that it can reciprocate back and forth within the cylinder. The piston divides its cylinder into two chambers and there is a fluid line interconnecting the chambers. The line is adapted to transfer fluid between chambers as a function of the movement of the piston. Within the line I have provided a control valve which is operated by actuation of either the throttle or the brake lever or both. The valve in one position permits the fluid transfer through the line, while in another position prevents fluid transfer and thereby provides a hydraulic lock that is to say, the piston cannot move relative to the cylinder.

The reciprocating motion of the piston within the cylinder provides for the necessary slack and when the control valve is actuated to block the fluid line, this slack is immediately eliminated because of the incompressibility of the fluid on either side of the piston.

A hydraulic arrangement such as described above is desirable because it provides the additional and important advantage of providing a cushioning or yielding effect as between cars. When the piston and cylinder are moved relative to each other, the fluid is transferred between the chambers through the fluid line. It takes a certain amount of work to cause this transfer of fluid and hence this will dissipate the energy due to the motion of one car relative to another.

The yielding effect, of course, is particularly important in yard operations to minimize the effects of impact when cars are being coupled together and also has importance under moving conditions in preventing any sharp impacts between cars. Another feature of the yielding effect is that it is highly useful in starting the train. As the cars start to move, the slack begins to run out gradually so that impact at the end of run out is minimized. This gradual run out causes a gradual pulling force to be exerted on adjacent cars. The foregoing is in contrast to conditions with conventional gear wherein the slack runs out quickly and the force is transferred from one car to another by impacts.

In addition to the foregoing the invention contemplates a novel manually operated throttle handle for use in the locomotive power control arrangement. The throttle is constructed in two parts so that the engineer can move one part relative to the other and thereby prevent or provide for slack between the cars. After the slack is taken out or put in, further rotation of the throttle will effect the increase or decrease in power output. In connection with the handle I have also provided a lock-out lever which will permit the engineer to move the throttle without effecting the slack control.

Another particularly important aspect of the invention is a flow control valve which is used in the fluid line on the piston and cylinder devices to meter the fluid flow as a function of the forces exerted on the fluid in the cylinder.

The details of the invention will be described below in connection with the following drawings, wherein:

FIGURE 1 is an elevational view partially in section showing an embodiment of the invention in the form of a piston and cylinder device having means to control fluid flow between chambers;

FIGURE 2 is a plan view partially in section showing a locomotive throttle for use in conjunction with the device of FIGURE 1;

FIGURE 3 is a diagrammatic view of a train air system modified to include the invention;

FIGURE 4 is an elevational, section view showing a slack control valve;

FIGURE 5 is a diagrammatic view showing an air system on a car modified to include the invention; and

FIGURE 6 is similar to FIGURE 2 except that certain movable parts of the throttle are shown in a different position.

In FIGURE 1, number 10 identifies the coupler device used to couple two railroad cars together. Impact force exerted upon the coupler device 10 causes draw bar piston 11, having enlarged central diameter 14, to move within draw bar cylinder 12. Fluid in draw bar chamber 13 is exhausted through port 15 in draw bar cylinder 12. Fluid under compression flows through hole 16 in gate valve 17, passing drain plug 20 and flow control valve 21, through port 23, into draw bar cylinder chamber 24. Continuing impact force on coupler device 10 moves bar piston 11 until enlarged central diameter 14 passes over and seals port 15 in draw bar cylinder chamber 13 of draw bar cylinder 12. Fluid in draw bar cylinder chamber 13, now completely captured, reacts against enlarged central diameter 14 of draw bar piston 11, terminating any further movement of draw bar piston 11 by absorbing additional force exerted on coupler device 10. Fluid in draw bar cylinder chamber 25, under compression, will escape to draw bar cylinder chamber 13 through slot 26 in draw bar piston 11.

Tension force exerted upon the coupler device 10 causes draw bar piston 11 having enlarged central diameter 14 to move within draw bar cylinder 12. Fluid in draw bar cylinder chamber 24 of draw bar cylinder 12 is exhausted through port 23, passing flow control valve 21, drain plug 20, through hole 16 in gate valve 17, and entering draw bar cylinder chamber 13 of draw bar cylinder 12 through port 15. Continuing tension force on coupler device 10 moves draw bar piston 11 until enlarged central diameter 14 passes over and seals port 23 in draw bar cylinder chamber 24 of draw bar cylinder 12. Fluid in draw bar cylinder chamber 24 of draw bar cylinder 12, now captured, reacts against enlarged central diameter 14 of draw bar piston 11, terminating any further movement of draw bar piston, 11, by absorbing any additional tension force exerted on coupler device 10.

In FIGURE 1, the inner wall of draw bar cylinder chamber is fitted with a keyway 28 in which key 27 in draw bar piston 11 rides to maintain a vertical position of coupler device 10 for proper alignment. Coil spring 29 is attached at one end to the base of draw bar cylinder 12 in draw bar cylinder chamber 25, and the other end 31 of the coil spring 29 is recessed into draw bar piston 11, and secured to draw bar piston 11. Coil spring 29 is designed to react as an emergency protective device against internal damage of the draw bar piston 11 or draw bar cylinder 12 should the captured fluid contained in chambers 13, 24, 25 and by-pass chamber 18 of draw bar cylinder 12 be insuflicient to insure normal fluid absorption of force originating at coupler device 10.

Coil spring 29 maintains the neutral position of enlarged central diameter 14 of draw bar piston 11, midway between port 15 and port 23, in draw bar cylinder 12,- when draw bar piston 11 is in position of rest.

In FIGURE 1, flexible hose 33 is connected to the pneumatic operating brake system. When pneumatic operating brake system is placed in applied position, pneumatic pressure travels through flexible hose 33 into pneumatic cylinder 32, depressing pneumatic piston 34 within pneumatic cylinder 32. Depressed pneumatic piston 34 in turn depresses gate valve 17, moving hole 16 in gate valve 17 out of alignment with by-pass chamber 18 in draw bar cylinder 12, thus, sealing 01f by-pass chamber 18 of draw bar cylinder 12, and preventing any flow of fluid from draw bar cylinder chamber 13 to draw bar cylinder chamber 24; thus, completely capturing fluid in chamber 13 and chamber 24 of draw bar cylinder 12. Captured fluid in draw bar cylinder chamber 13 and captured fluid in draw bar cylinder chamber 24 prevent, by reactive pressure upon enlarged central diameter 14 of draw bar piston 11, any motion of draw bar piston 11 through impact or tension force received by draw bar piston 11 through coupler device 10. In this way, a rigid coupling is achieved, eliminating the possibility of the creation of an impact force, when pneumatic operating brake system is applied to decelerate the velocity of objects in motion equipped with this invention.

In FIGURE 1, draw bar cylinder head is securely bolted to draw bar cylinder 12 and O-ring 36 is located between joined surfaces of the draw bar cylinder head 35 and draw bar cylinder 12 to prevent escape of fluid between these joined surfaces. A sealing washer 37 is located between draw bar cylinder head 35 and draw bar piston 11 to prevent escape of fluid. Also located in draw bar cylinder head 35 is a dirt seal washer 38 to prevent admission of dirt or foreign objects into chambers of draw bar cylinder 12. A filler plug 39 is located in the top of draw bar cylinder 12 for the purpose of filling chambers of the draw bar cylinder 12 with fluid. This filler plug 39 is provided with a sealing washer 40 to prevent escape of fl uid from the chambers of draw bar cylinder 12. By-pass chamber housing 41 is securely bolted to external face of draw bar cylinder 12 positioned to align by-pass chamber 18 with port 15 and port 23 in draw bar cylinder 12. Two grommet type, sealing washers 42 and 43 prevent escape of fluid where this alignment occurs. A flow control valve 21 is located in by-pass chamber housing 41 to control velocity of the flow of fluid through by-pass chamber 18 by reducing the area of bypass chamber 18. Flow control valve 21 is equipped with a position retaining lock nut 44 and sealing washer 45 to prevent escape of fluid from bypass chamber 18 at control valve 21. The drain plug 20 is located in by-pass chamber housing 41 to facilitate the drainage of fluid from the chambers 13, 18, 24 and 25 of the invention. A sealing washer 19 prevents escape of fluid through drain plug 20. A compression spring 46 is located in 'by-pass chamber housing 41 at the base of gate valve 17 and is used to return gate valve 17 to an open position when pneumatic pressure is relieved from pneumatic cylinder 32.

Draw bar cylinder 12 is secured to center sill 47 by pin 48, providing draw bar cylinder 12 a radial movement on pin 48.

In FIGURES 2 and 6, there is shown a throttle control arm 49 that rotates upon a shaft 50 within certain limits of rotation which are defined by a quadrant 51. This quadrant 51 is calibrated by numbered notches 53 of the periphery of the quadrant 51. These numbered notches 53 provide a means for measuring the amount of power applied for the purpose of acceleration. Exerting a pulling force upon this handle segment 52 will cause it to move clockwise along the quadrant 51 within the terminal limits of the quadrant 51. A pushing force in the opposite direction on the handle segment 52 will cause it to travel counterclockwise along the quadrant 51 in the reverse direction which will decrease the motive power and effect a deceleration of the selfpropelled unit, as will be further explained hereinbelow. The control arm 49 is formed in two segments, the handle segment 52 is joined to the hub segment 54 by means of a pin 55 located on the hub segment. The handle segment 52 is provided with a hole 56 which receives the pin 55 attached to the hub segment 54. A pulling force upon this handle segment 52 will cause it to rotate around the pin 55 but only to such a point where it will be in alignment with the hub segment 54. This restriction is provided to insure that a pulling force will cause an immediate rotation of the control arm 49, and in turn provide immediate acceleration of the self-propelled unit to occur at any point within the limitations of travel of the control arm 49 in this direction, as defined by the limits of the quadrant 51. When a pushing force is applied to the handle segment 52 to effect a deceleration of the self-propelled unit, the handle segment 52 will rotate around the pin 55 to a defined limit 57 as clearly shown in FIGURE 6; thence, a continued pushing force upon the handle segment 52 will cause the hub segment 54 also to rotate causing a deceleration to occur at any place along the quadrant 51 within the limitations of the quadrant 51.

This rotation of the handle segment 52 around the pin 55 toward a decelerating position will achieve two resultant actions. As the handle segment 52 is rotated toward the decelerating positions, an insulated metal contact plate 58 located in the handle segment 52 is moved against an insulated metal contact shoe 59, energized with a positive charge of DC. current. This insulated metal contact shoe 59 has a fixed location in the hub segment 54. Continued rotation of the handle segment 52 causes the insulated metal contact plate 58 to travel against the insulated slack control shoe 60 (see FIGURE 6) establishing a circuit through the insulated slack control shoe 60 which feeds this positive charge into an adjacent slack control relay 61, FIGURE 3, having a sustained negative charge.

The relay 161, thus energized, will open the exhaust port in a three-way valve 62, FIGURE 3, causing decrease of pressure in the slack control line pipe 63, FIGURE 3. This reduction of pressure in the slack control line pipe 63, FIG- URE 3, will cause the slack control valve 64, FIGURE 3,

hereinafter described in detail, to close a gate valve which functions similarly to the gate valve 17 previously described and shown in FIGURE 1, and thereby lock out slack motion of the draw bar piston 11 'and thus eliminate any slac k motion of this draw bar piston.

A continued pushing pressure on the handle segment 52 in the position shown in FIGURE 6 will cause motion of the hub segment 54 on its shaft 50 and consequently deceleration. In this manner, the slack control cushioning draft gear, FIGURE 1, on the cars and the self-propelled unit will operate and eliminate all slack movement within slack control cushioning draft gears, prior to any attempted runin of slack caused by the effect of deceleration. When the desired point of deceleration has been achieved through a reduction of power only, a pulling force exerted upon the handle segment 52 will cause motion of the handle segment 52 around the pin 55 disengaging the insulated metal contact plate 58 from the slack control contact shoe 60 which in turn de-energizes the slack control relay 61, FIGURE 3, closing the exhaust port of the three-way valve 62 which in turn causes the pressure in the slack control line pipe 63 and the slack control valve 64, FIGURE 3, to be restored to their normal pressure. This, in turn, as will be hereinafter described, restores all slack movement within the slack control cushioning draft gear, FIGURE 1, which then allows it to hydraulically absorb and cushion all forces exerted upon it.

The continued pulling force exerted upon the handle segment 52 which has now reached its limit of rotation on the pin 55 places the handle segment 52 in straight alignment with the hub segment 54 (see FIGURE 2) and additional pulling force exerted upon the handle segment 52 will rotate the control arm 49 on its shaft in the direction of acceleration.

With reference to FIGURE 2, the lock lever 66 permits the throttle control arm 49 to be rotated without affecting the slack control. The lock lever 66 extends from one side of the hub segment 54 in an angular position in relation to the handle segment 52. This lock lever 66 is spring-loaded to maintain this angular or disengaged position. By gripping the finger grip of the lock lever 66 and drawing it toward and against the side of the handle segment 52 the spring-loaded lock shaft 67 is depressed into the hub segment 54 and engages the side wall of the handle segment 52 on one side of a pointed projection 68 preventing any movement of the handle segment 52 around the pin 55. In this lock-out position, of the lock lever 66, the slack control cushioning draft gear invention, FIGURE 1, cannot be activated until the lock lever 66 is released and the springlock shaft 67 returns it to a disengaged position.

The lock lever 66 also can be utilized to permit rotation of the throttle control arm 49 while the slack is locked out. A pushing force exerted upon the handle segment 52 in a direction of deceleration will cause it to rotate around the pin to the position shown in FIG- URE 6 thereby locking out slack. By maintaining this angular position of the handle segment 52 and drawing the finger grip handle of the lock lever 66 toward the handle segment 52 while it remains in the angled position, the spring-loaded lock shaft 67 engages one side of the pointed projection 68 preventing any movement of the handle segment 52 around the pin 55 on as shown by the dotted lines in FIGURE 6. In this lock-in position, the

control arm 49 cannot be rotated without affecting the lock-out condition of the slack. Until the lock lever 66 is released and the spring-loaded lock shaft 67 returns the lock lever 66 to a disengaged position. A pulling pressure exerted now upon the handle segment 52 will align it with i the hub segment 54, the position shown in FIGURE 2, and continued pulling will cause entire control arm 49 to rotate and increase acceleration of the self-propelled unit.

A dead-man control lever 69 when released will cause the train brakes to be applied and the slack locked out. In FIGURE 2 a dead-man control lever 69 is hinged on a pin 70 extending through the handle segment 52 adjacent to the pin 55. This dead-man control lever 69 is spring-loaded 71 to elevate it from the handle segment 52 to an angular position above the handle segment 52 when a manual pressure is removed. The piston positioning pin 72 extends through one side wall of the deadman control lever 69 and into a cavity 73 of the segment 52, where it passes through a vertically elongated hole 74 in a piston 75, movable within the cavity 73. This pin 72 continues through the handle segment 52 and through the opposite side wall of the dead-man control lever 69. The left hand end of the piston 75 is provided with an insulated contact plate 76 which slides on an exposed surface of the handle segment 52 above and clear of the insulated slack control contact plate 58. The dead-man control lever 69, when depressed toward the handle segment 52, the position shown in FIGURES 2 and 6, will rotate on the hinge pin causing the piston positioning pin 72 to travel in an arc. The piston positioning pin 72 riding in the vertcally elongated slot 74 causes the piston with attached insulated contact plate 76 to travel to the right into the cavity 73, breaking the electrical contact between the insulated contact plate 76 and the fixed contact shoe 59. This insulated contact plate 76 of the piston 75 has a radius of curvature on its contacting surface which permits it to make contact with this fixed shoe 59 at any position around a radius described by the motion of the handle segment 52 around the pin 55 when the dead-man control lever 69 is released and elevated by its springloading.

As the dead-man contact plate piston 75 travels further into the cavity 73, it depresses a compression spring 71 located between one end of the dead-man contact piston 75 and the bottom face of the cavity 73. The spring loading of the dead-man contact piston 75 will, upon relief of manual pressure upon the dead-man control lever 69, elevate this lever by exerting a pressure upon the sliding dead-man contact piston 75 causing it to travel to the left out of the cavity 73 forcing the piston control pin 72 to travel in an are describing a radius of the hinge pin 70, and also forcing the insulated contact plate 76 against the fixed contact shoe 59, and at the same time, forcing the insulated contact plate 76 against the fixed dead-man relay contact shoe 77 and also forcing it against the fixed slack control relay shoe 60, thus completing an electrical circuit between the fixed contact shoe 59 and the dead-man relay fixed contact shoe 77 and also completing an electrical circuit between the fixed contact shoe 59 and the slack control relay fixed contact shoe 60.

In FIGURES 2 and 6, the quadrant 51 around which this control arm 49 traverses is provided with notches 53. The side face of these notches 53 is inclined and all corners are rounded and the notches are so spaced, in relation to one another, that they will allow a springloaded notch key 78, having a rounded end 79 that will allow it to engage itself within the various notches located around the quadrant 51 in such a manner that a traversing motion performed by the control arm 49 or the handle segment 52 in either direction around the periphery of the quadrant 51, will cause a sequence of disengagement and engagement in a repetitive order, of this notch key 78 by its rounded end 79 riding against the inclined side surface of the notches 53, in which it is engaged, which moves the notch key 78 against a notch key compression spring 80. Compression of this spring 80 allows a displacement of the notch key 78 from the notches 53 to occur until the rounded end 79 is aligned with the next adjacent notch 53. The compression spring 80 reacts against a shoulder 81 on the notch key 78, depressing this rounded end 79 into the next adjacent notch. The notch key spring 80 is retained within the cavity 82 by a tubular plug 83 which is threaded and screwed into this cavity 82. A thumb button 84 on one end of the notch key 78 is extended when the rounded end 79 of the notch key 78 is disengaged from the notch 53. The compression spring 80 then exerts a force upon the shoulder 81 positioning the notch key 78 within this next adjacent notch and drawing the thumb button 84 against the tubular threaded plug 83. This movement of the round end 79 of the notch key 78 in and out of the notches 53 will provide a method of measuring by notches the traversing movement of the control arm 49 around the quadrant 51 by numbering each notch beginning with 0, to indicate the olf position of the control arm 49 and successively numbering each notch 53 from that point to the extreme opposite end of the quadrant 51.

By exerting a thumb pressure upon the thumb button 84, a disengagement of the notch in which it is positioned will be prevented for the purpose of sustaining a definite desired position of the control arm 49 or a definite position of the handle segment 52 along the periphery of the quadrant 51.

As shown in FIGURES 2 and 6, the dead-man relay contact shoe 77, fixed common feed contact shoe 59, and the slack control relay contact shoe 60 are formed Wit-h a curved contact end to facilitate a more complete individual contact between these shoes and the insulated, metal contact plates 58 and 76. The insulated, metal contact shoes 59, 60 and 77 are all formed with a shoulder 85 at the top and bottom of each shoe, which secures them within an insulated housing 86 which is formed with parallel vertical oblong openings through which the contact shoes 59, 60 and 77 protrude to the limit of the shoulder 85 of each individual shoe. Each contact shoe 59, 60 and 77 is spring-loaded with spring 87 to retain this positioning and provide a flexibility of the contact shoe to insure a more definite contact with a minimum of friction. Each of the three contact shoes 59, 60 and 77 are formed with a round shaft 88 extending from a posterior surface of the contact shoes 59, 60 and 77, and extends through the compression springs 87 of each shoe and then through an individual round opening 89 in the removable back plate 90 of the insulated housing 86. This back plate 90 is formed to provide sufficient bearing surface, in each individual round opening 89 for each shaft 88. At the exposed end of each shaft is a metal contact clamp 88A which provides a means for attaching an insulated electrical wire as shown in the schematic drawing, FIGURE 3.

Another and preferred type of gate valve is shown in detail in FIGURE 4. In FIGURE 4 the preferred gate valve is contained within the slack control valve generally designated 64, and is operated in the manner set forth below. The position of the parts of the valve of FIG- URE 4 is for the condition of maintaining slack between the cars. The piston 91 moves within a cylinder 92 to an open or closed position. 'In the slack lock-out condition closed position the piston 91 is moved to seal off the ports 93 and 94 to prevent flow of fluid through the piston 91. To allow for slack, the ports 93 and 94 of the piston 91 open into a cavity 95. The cavity 95 has a central diameter larger than the diameter of the cavity 95 at its ports 93 and 94. A sphere 96 having a diameter greater than the diameter of the ports 93 and 94, but less than the central diameter of the cavity 95, is freely retained within this cavity 95 and will seat itself in one or the other ports 93 and 94 as dictated by the direction of the flow of the fluid through this cavity. The sphere 96 has grooves 97 formed into its surface in an interlaced pattern. The grooves are open at their intersections. The grooves 97 are provided to allow the fluid to flow by when the flowing fluid seats the sphere in either port 93 or 94. The grooves 97 in permitting flow of fluid act like the hole 16 (FIGURE 1) in permitting flow of fluid. The piston 91 is provided with elastic wipers 98 and 99, and is formed as a hollow cylindrical container 100. Two sets of identical semicylindrical inserts 101 and 102 form the cavity 95. The cylindrical plug 103 is inserted into the hollow cylindrical container 100 and a locking pin 104 is inserted in a hole in the wall of the hollow cylindrical container 100 passing through the cylindrical plug 103 and engaging in a hole in the opposite wall of the hollow cylindrical container 100. This assembled piston 91 is then screwed on to the threaded end of the piston rod 105 that has been passed through the plate 106 and the static seal of 107 of this plate 106. The piston 91 is then inserted into the cylinder 92 after the compression spring 146 has been placed in the base of the cylinder 92. The piston 91 is then in position where it intersects with the by-pass chamber and the ports 93 and 94 are secured in alignment and open to these by-pass chambers. An O-ring 108 is located between the external surface of the by-pass chamber housing 149 and one external surface of the plate 106 as a seal.

The threaded end of the piston rod 105, to which the piston 91 is attached, extends out of the pneumatic slack control valve housing 109. This housing 109 is positioned against the other external surface of the plate 106 with an O-ring 110 positioned between these surfaces as a seal. Threaded bolts 111 and 112 pass through a flange on the pneumatic slack control valve housing 109 and through the plate 106, and are screwed into the by-pass chamber housing 149 to complete the assembly of the slack control valve 64.

The piston rod 105 passes through a static seal 113 located in the slack control valve housing 109 and through a piston 114 having an elastic wiper 115 in the throttle slack control cylinder 116 and continues through an elastic wiper 117 in the slack control valve housing 109, then into a piston 118 having an elastic wiper 119 in the brake-slack control cylinder 120.

Pressurized air released from the brake control valve, FIGURES 3 and 5, enters the slack control valve through brake port 121, FIGURE 4, and continues to the brakeslack control cylinder 120 exerting a pressure upon the piston 1-18, moving the piston connecting rod 105 which closes the piston 91.

Brake control valve, FIGURES 3 and 5, in exhaust position will relieve this air pressure upon the piston 118 and allow compression spring 146 to return cylinder 91 to an open position. Pressurized air from the throttleslack control pipe, FIGURES 3 and 5, enters the slackcontrol valve 64 at throttle port 122 to the reservoir control cylinder 123 moving the reservoir control piston 124 and its connecting rod, which in turn moves slide valve 125 and positions the exhaust port 126 of the slide valve 125 to allow air pressure in throttle-slack control cylinder 116 to be exhausted, allowing compression spring 146 to place cylinder 91 in open position. Displaced reservoir control piston 124 now allows pressurized air to enter slack-control valve reservoir 127 until the pressure of the air in the reservoir 127 is equal to the pressure of the air entering the throttle port 122. When this air pressure at the throttle port 122 is reduced by energizing the slack control relay, FIGURE 3, connected to the throttle control arm 49, FIGURE 2, by a movement of the handle segment 52, pressurized air escapes from the reservoir 127 through the reservoir control cylinder 123 and will move the reservoir control piston 124 to a seated and sealed position.

The slide valve 125 connected to the piston 124 by its rod now is moved by this motion of the piston 124 to a position that will allow remaining pressurized air in the slack-control valve reservoir 127 to enter the throttle-slack control cylinder 116 and move the piston 114 in this cylinder 116, and the piston connecting rod 105 closes the cylinder 91. When the throttle-slack control relay, FIGURE 3, is again de-energized by a movement of the handle segment 52, and air pressure in the throttle-slack control pipe is restored to its normal pressure, air again enters throttle port 122 and continues to the reservoir control cylinder 123 displacing and unseating the reservoir control piston 124 which through its connecting rod moves the slide valve 125 again to an exhaust position to allow air pressure in throttle-slack control cylinder 116 to be exhausted allowing the compression spring cylinder 91 to be in' open position. Displaced reservoir control piston 124 now allows pressurized air to enter slack-control valve reservoir 127 until the pressure of the air in the reservoir is equal to the pressure of the air entering the throttle port 122.

I claim:

1. In a railway car having a center sill:

an elongated draw bar, the draw bar having an interiorly extending cavity, said cavity forming a cylinder within the draw bar;

pivot means connectingthe draw bar to the center sill;

a piston in said cylinder dividing the cylinder into two chambers;

means supporting the piston in the cylinder for reciprocating motion therein;

a railway car coupler;

a rod extending through an aperture in said cylinder and connecting said coupler with said piston for unitary motion therewith, the motion of the coupler and piston providing for slack;

means on said draw bar forming a fluid passage connecting the chambers on the opposite sides of said piston;

a gate valve in said passage movable to one position for permitting flow of fluid through the passage to permit said reciprocating motion of the piston and coupler and movable to another position for preventing flow of fluid to lock the piston and coupler against said motion; and

mechanism connected with said valve for selectively moving the same to either of said positions.

2. A construction in accordance with claim 1 wherein said mechanism includes a spring to move the valve to the position permitting the flow of fluid and further includes an air operated piston to move the valve to the position preventing the flow of fluid.

3. A construction in accordance with claim 2 wherein said air operated piston has means connecting the same to the air supply of the railway car.

4. A construction in accordance with claim 1 and further including a flow control valve in said passage to control the flow of fluid in said passage.

5. A construction in accordance with claim 1 wherein said means supporting the piston in the cylinder comprises a key on said piston engaging a keyway on said cylinder.

6. In a pair of adjacent railroad cars:

a pair of hydraulic fluid cylinders and means respectively connecting the cylinders to ends of adjacent cars;

a pair of pistons respectively disposed within the cylinders for reciprocating motion along the cylinder axis, the piston dividing its cylinder into two chambers and the chambers containing hydraulic fluid therein;

a air of couplers connected together;

means connecting said couplers respectively with said pistons for reciprocating motion theerwith, the reciprocating motion providing for slack between the adjacent cars; and

means connected with each cylinder including a hydraulic fluid line making a fluid transfer connection between the chambers to conduct fluid between the chambers and being disposed to be in communication with the chambers at all positions of the piston along the cylinder axis for said fluid transfer and control mechanism in the fluid line alternatively operable at any position of the piston along the cylinder axis to permit or stop the flow of fluid thru said line, the fluid when stopped preventing said reciprocating motion and thereby preventing slack and the fluid when flowing in the line permitting the reciprocating piston motion and thereby permitting slack.

7. A construction in accordance with claim 6 wherein said control mechanism is a reciprocating member connected to a pair of piston and cylinder means commonly connected to reciprocate the member.

8. A construction in accordance with claim 6 wherein said means connecting a cylinder to a car includes pivot means providing for the cylinder to move relative to the car.

9. A construction in accordance with claim 8 wherein said control mechanism is a control valve movable to a position wherein the rate of fluid is Zero and movable to a position wherein the rate of fluid flow is a finite value.

10. Slack control mechanism for a railroad car having a sill and a coupler comprising:

a hydraulic fluid cylinder;

means for fixedly connecting the cylinder to the sill of the car;

a piston disposed within the cylinder for reciprocating motion along the cylinder axis, the piston dividing the cylinder into two chambers, the chambers being adapted to contain hydraulic fluid therein;

means for connecting the piston to the coupler for reciprocating movement therewith, the reciprocating motion of the coupler and piston providing for slack; and

means connected with the cylinder including a hydraulic fluid line making a fluid transfer connection between said chambers to conduct fluid between the chambers and being disposed to be in communication with the chambers at all positions of the piston along the cylinder axis for said fluid transfer, and control mechanism in the fluid line alternatively operable at any position of the piston along the cylinder axis to permit or Stop the flow of fluid thru said line, the fluid when stopped preventing said reciprocating motion and thereby preventing slack and the fluid when flowing in said line permitting said relative movement and thereby permitting slack.

11. Slack control means for a railroad car having a sill and a coupler comprising:

a hydraulic fluid cylinder element;

a piston element disposed within the cylinder for reciprocating motion along the cylinder axis, the piston dividing the cylinder into two chambers and the chambers being adapted to contain hydraulic fluid therein;

means for fixedly connecting one of said elements to the coupler for reciprocating movement therewith, the reciprocating motion of the element and coupler providing for slack;

means for fixedly connecting the other of said elements to the sill of the car; and

means including a hydraulic fluid line making a fluid transfer connection between said chambers to conduct fluid between the chambers and being disposed to be in communication with the chambers at all positions of the piston along the cylinder axis for said fluid transfer and control mechanism in the fluid line alternatively operable at any position of the piston along the cylinder axis to permit or stop the flow of fluid thru said line, the fluid flow when stopped preventing said reciprocating motion and thereby preventing slack and the fluid when flowing in said line permitting said relative movement and thereby permitting slack.

References Cited UNITED STATES PATENTS 1,419,430 6/1922 Wheatley 188-97 X 1,484,193 2/1924 Scott 18897 X 2,827,186 3/1958 Waite 18897 X 2,909,291 10/1959 Gibson 213-43 3,142,363 7/ 1964 Tamini 18897 DRAYTON E. HOFFMAN, Primary Examiner. 

